This invention relates generally to dishwasher racks, and more particularly to a fence for a dishwasher rack which is selectively movable between a folded or inoperative position where it extends parallel to the bottom wall of the rack and an upright or operating position.
Dishwashers of the household type are generally manufactured to have a standardized set of exterior dimensions, particularly the height and width, to allow them to be installed in a standardized under-counter location. Because of the need for a certain amount of space at the bottom for the operating mechanism, the interior of the tub, therefore, has an almost standardized set of dimensions which result in the usual interior configuration of a sliding bottom rack located as near to the bottom of the tub as possible, together with a sliding upper rack positioned near the top wall of the tub in a location to allow it to accept as large an article as possible, subject to clearance with the top wall, as well as avoiding interference with larger items stacked in the lower rack.
The racks are generally formed from a steel wire coated with a plastic material, such as vinyl or nylon, which serves not only to protect the steel from rust but also prevents chipping and breakage of glass and china articles placed in the racks. The wires of the racks are generally configured in the form of a basket having side walls and a bottom wall which may be contoured to allow articles to assume a tilted position, particularly in the case of the upper rack, which is generally used for cups, saucers, and glasses, as compared to a lower rack normally used for larger plates and pots and pans, with silverware being placed in a separate receptacle generally attached to the lower rack. The racks are also provided with fences or members having upwardly projecting pins or wires with free ends to separate the stacked items, and this may create a problem if the load to be washed does not fit a predetermined arrangement of large and small articles. This is particularly true in the case of the upper rack, which is usually used for washing small articles. Thus, several fences may be mounted on the upper rack for separating and positioning small saucers, as well as holding glassware either against the side wall of the rack or by having some glasses fitted over one or more pins in an inverted position to prevent movement during washing, which could cause adjacent glasses or the like to contact each other and chip or break.
At times, the presence of a fence of upstanding wires, particularly on the upper rack, may not be suitable for the items to be loaded in the upper rack, and for this reason it has been proposed to make one or more fences on the upper rack, or even the lower rack, foldable so that they may be moved so that the wires are either in a stored or inactive position adjacent the bottom wall of the rack, or in an upright position for holding and spacing articles in the customary manner.
One of the earliest patents showing such an arrangement is U.S. Pat. No. 3,126,098, wherein the upper rack has a set of fence members formed of wire which are hinged to move between two positions, one of which conforms with the bottom of the rack and the other being limited by engaging a stop formed on the side wall of the rack. The hinge is formed by having one of the movable rack wires bent into a circle around a fixed wire on the bottom of the rack. With this arrangement, there is no positive means to hold the fence in the erect position, and the use of a direct contact hinge will result in rapid wear of the protective coating on the wire.
The next improvement over this is shown in U.S. Pat. No. 3,269,548, which is similar to the above structure except that the hinges are formed in separate hinge clips attached to the bottom rack and a flexible spring on the side wall has a notch to receive a fence wire on the end as a detent to hold it in the upright position.
A further improvement over the above arrangements is shown in U.S. Pat. No. 3,752,322, in which the fence has a flexible end wire extending against an arcuate retainer having a plurality of ridges and notches formed in it so that the fence may be held in a plurality of adjusted rotary positions while rotating about an axis determined by a hinge member on the bottom of the rack. In both of the latter two designs, the detent is formed by a resilient member and it is easily possible for the fence to be accidentally moved when pieces are being loaded on the upper rack.
Another arrangement is shown in U.S. Pat. No. 3,402,975, in which the dishwasher is of the top-loading type, and therefore has an upper rack that folds back to allow access to the lower rack. The upper rack includes a foldable fence having a horizontal wire and a plurality of vertical wires. The horizontal wire carries an index member fixed against rotation of the wire by having a portion grasping one of the vertically projecting wires. This index member engages a hub which pivots the wire, and interlocking detent means between the index member and the hub serve to hold the fence in place.
Still another arrangement is shown in U.S. Pat. No. 4,606,464, in which a rather complex mounting clip is used to provide a hinge and spring-loaded detents which engage laterally extending projections in the vertical wires of the fence.
Another arrangement which has been used to avoid the problem of providing rotating bearings and spring-loaded hinges is shown in U.S. Pat. No. 4,046,261, assigned to the assignee of the present invention. In this case, the rack is provided with a plurality of special support structures and individual fences may be inserted into grooves in these structures so that the fences may be either completely removed from the rack or inserted in the desired position.